xml-无法将形状设置为TextView的背景

Question

I'm trying to set a transparent circle with a stroke as the background of a TextView in android:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TextView
        android:id="@+id/status"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="24dp"
        android:background="@drawable/decibel_circle"
        android:text="30 dB"
        android:fontFamily="sans-serif"
        android:textColor="@android:color/black"
        android:textSize="70dp" />
</RelativeLayout>

And this is the shape I want to use, located in decibel-circle.xml

<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <shape xmlns:android="http://schemas.android.com/apk/res/android"
        android:shape="oval">
    <stroke
        android:width="5dp"
        android:color="#F44336">
    </stroke>
    <solid android:color="@android:color/transparent"/>
    <size
        android:width="36dp"
        android:height="36dp" />
    <corners android:radius="12dp" />
    </shape>
</selector>

The problem is that the shape is never shown, neither in the preview nor when I run my app. What am I doing wrong?

Answer 1

in your decibel-circle.xml remove selector just use shape alone

Use this only

 <shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="oval">
<stroke
    android:width="5dp"
    android:color="#F44336">
</stroke>
<solid android:color="@android:color/transparent"/>
<size
    android:width="36dp"
    android:height="36dp" />
<corners android:radius="12dp" />
</shape>